1. Field of the Invention
This invention relates generally to an interface for a manual controller and a locomotive and, more specifically, to a system, apparatus, and method for controlling a locomotive with an automatic control system.
2. Background of the Invention
Railroads are beginning to pursue locomotive “cruise control” systems for operating locomotives. These systems will require a crew member to engage or disengage the system and will also require a computer to drive the throttle, dynamic brake, and air brake systems. These systems may be implemented in, for example, a lead locomotive of a train or a pusher locomotive. In these existing systems, a crew member would normally be present with a computer-controlled system that would have a need to control the throttle and brake of the locomotive.
This implementation poses a problem in that, when a computer controls the throttle and brake systems and an operator is allowed to disengage the computer-controlled system, the control settings of the manual controls may not match the computer-controlled system settings when it is disengaged. This mismatch of control settings can cause a number of problems, including an undesired jump up or down in a throttle notch, resulting in an undesired acceleration or braking action. An undesired jump up of a throttle notch may result in increased speed or high in-train forces. An undesired jump down in a throttle notch may be problematic if the train is climbing a steep grade, since a sudden loss of power could stall the train on the grade.
Further, if the dynamic brake or independent brake settings do not match the computer-controlled system settings, there may be a reduction in braking force that causes an undesired increase in speed. Since neither the dynamic brake nor independent brake have detents in the handle position, it is difficult to indicate to the crew where to place the handle when disengaging. If the brake handle setting does not match the computer-controlled automatic brake setting, there may be an undesired release of the train air brakes. If an undesired release occurs, the train could increase in speed and a second pneumatic brake set would have to occur to reapply the brakes. This could be an undesirable situation because it reduces the brake pipe to a low level and could reach the point of not being able to command further reductions.
For at least the foregoing reasons, there is a need for a system, apparatus, and method that can control the throttle, dynamic brake, air brake, distributed power system, and/or other manual controls normally operated by a crew member.